Non-Wesen beings are all creatures that are not Wesen and include ghostly, demonic, and spiritual creatures.
Only three types of non-Wesen are known, these being:
Ghosts are non-Wesen creatures that conform to ideas set out in classic stories of dead spirits that are unable to pass on to the afterlife. Ghosts can disappear and create illusions, and they may also hide their real appearance, much like a Wesen. La Llorona and her three kids are the only known examples.
Demons are non-Wesen creatures that inspired the legends, myths, and religious figures of evil beings that live inside the Earth and are normally related to fire and the dead. Judging from the only known Demon encountered, their abilities include spitting fire, teleportation, and causing earthquakes. Volcanalis is the only known example.
Spirits are non-Wesen that occupy a man-shaped body made from a single material or are able to possess a human's body. Despite being powerful creatures that are easily capable of killing, they aren't strictly malign. Spirits can be summoned through specific types of prayer or possess someone who was dead and then revived soon after. Spirits are different from ghosts in that some appear to have never been living creatures. The Golem, Mishipeshu, and Jack the Ripper are known examples.